Question: Molly and Torry like to eat ice cream sandwiches. In one week, Molly ate $5$ ice cream sandwiches, and Torry ate $n$ ice cream sandwiches. They ate a total of $12$ ice cream sandwiches all together. Write an equation to describe this situation. How many ice cream sandwiches did Torry eat?
Molly ate ${5}$ ice cream sandwiches, and Torry ate an unknown number of ice cream sandwiches, which we're calling ${n}$. All together, they ate ${12}$ ice cream sandwiches. We can represent Molly and Torry's ice cream sandwiches as a sum: ${5} + {n}$ We know that together they ate ${12}$ ice cream sandwiches in one week. The following equation matches this situation: ${5} + {n} = {12}$ Other ways to represent the situation with an equation include: ${n} + {5} = {12}$ or ${12} - {n} = {5}$ or ${12} - {5} = {n}$. Now we can solve for ${n}$. Subtract ${5}$ from both sides of the equation to get ${n}$ by itself: $\begin{aligned} {5} -{5} + {n} &= {12}-{5} \\ \\ {n} &={7} \end{aligned}$ The following equation matches this situation: ${5} + {n} = {12}$ Torry ate ${7}$ ice cream sandwiches.